A joint project of the Graduate School, Peabody College, and the Jean & Alexander Heard Library

Title page for ETD etd-05182018-170119


Type of Document Dissertation
Author Arutt, Charles Nathan
URN etd-05182018-170119
Title Mechanisms of Ionizing Radiation Response in Silicon Piezoresistive Micromachined Cantilevers
Degree PhD
Department Electrical Engineering
Advisory Committee
Advisor Name Title
Ronald D. Schrimpf, Ph.D. Committee Chair
Bridget R. Rogers Committee Member
Daniel M. Fleetwood Committee Member
Jim L. Davidson Committee Member
Michael L. Alles, Ph.D. Committee Member
Robert A. Reed Committee Member
Keywords
  • Semiconductors
  • Ionizing Radiation
  • Total Ionizing Dose
  • X-rays
  • Silicon
  • Hydrogen
  • MEMS
  • Resonator
  • Piezoresistivity
  • Radiation Effects
Date of Defense 2018-05-02
Availability unrestricted
Abstract
A T-shaped, asymmetric, piezoresistive, micromachined, resonating cantilever is used to investigate the effects of 10-keV X-rays on resonance frequency and resistivity. Total-ionizing-dose-induced resonance frequency and resistivity shifts depend on dopant type and concentration, as well as dose-rate. Lower rate exposures produced up to 4-times more negative frequency shifts and 3-times more positive resistivity shifts than higher rate exposures in devices with lower doping. Devices that were hydrogenated in a steam bath for 1 h showed shifts similar to those of control (not hydrogenated) devices at higher dose rates, and larger shifts than control devices at lower rates. All devices recovered to levels close to pre-irradiation after several hours of post-irradiation annealing. The dose-rate dependence is attributed to differences in carrier concentration and mobility caused by varying efficiencies of the depassivation of dopants by hydrogen at higher and lower dose rates and/or surface charging effects, and the subsequent differences in Young's modulus and shear elastic constants of silicon that occur as a result. Many of these processes are similar to effects that lead to ELDRS in linear bipolar transistors, emphasizing the need to include low-dose-rate testing of MEMS devices when considering them for use in space systems.
Files
  Filename       Size       Approximate Download Time (Hours:Minutes:Seconds) 
 
 28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access 
  carutt.pdf 3.03 Mb 00:14:01 00:07:12 00:06:18 00:03:09 00:00:16

Browse All Available ETDs by ( Author | Department )

If you have more questions or technical problems, please Contact LITS.